Both in response to government regulations and a general desire for safety, rope grabs or similar devices have become a requirement for workers working in elevated positions. Such rope grabs typically fasten to a safety belt or safety harness fastened about the worker via a lanyard. The rope grab is then attached to a safety line which is in turn fastened independently of the scaffold or other movable structure upon which the worker may be working.
Prior art devices have proven less than totally acceptable for several different reasons. Some devices require the worker to manually adjust the rope grab on the safety line as the worker moves vertically. Other known prior art devices merely use a pivoting arm which is attached to the lanyard at one end and at the other end which bears against the rope. Such a device utilizes the weight of the falling worker to pivot the arm into contact with the safety line in order to provide a braking effect. It can be appreciated in such a device, however, that if the rope grab freely slides down the safety line at a rate equal to the speed of the falling worker, no stopping force can be applied. One known prior art device does provide a system whereby both inertia stopping and positive actuated stopping are provided. This device, however, does not allow the rope grab to be placed on a safety line intermediate the ends of the safety line. Due to the tubular nature of such a prior art device, the rope grab must be placed over the end of the rope. Such a device is often less than desirable as it is commonly necessary to attach the rope grab at some point intermediate the ends of the safety line.
Therefore, it is an object of this invention to provide a rope grab which may be easily attached to the safety line intermediate the ends thereof. It is a further object of this invention to provide a rope grab which utilizes both inertia and direct actuation for stopping. It is yet another object of this invention to provide a rope grab which does not cause damage to the safety line. Still another object of this invention is to provide a rope grab which prevents roll-out of the lanyard attaching hook. It is yet another object of this invention to provide a rope grab wherein the abruptness with which the braking force is applied may be varied.